The present disclosure relates to a safety device for controlling release of pressurized fluid from a vessel of the type having an open end with a closure removable for open access to the contents of the vessel. Pressure vessels of this type are often employed for filtering fluid through filter elements disposed within the pressure vessel and which require periodic removal for cleaning or replacement of the filter. The vessel typically contains an inlet and outlet connected in line in a fluid system for passing fluid under pressure through the filter elements contained within the vessel. Such pressure vessels commonly employ a header or closure plate disposed over an open end of the pressure vessel and secured thereto by fasteners such as bolts or toggle clamps and sealed over the end of the pressure vessel by a seal such as an O-ring or gasket.
A leak in the closure or lid seal can permit undesired release of pressurized fluid and thus create a hazard to the user. Also, in the event the vessel is not completely de-pressurized before the operator initiates release of the fasteners or clamps a residual pressurized fluid escaping between the flange and the undersurface of the cover plate as the fasteners are released can create a hazardous condition for the operator.
Thus, it has been desired to provide a way or means of reducing the hazard of escaping fluid under high pressure from a pressure vessel from a seal leak or upon depressurizing for removal of the vessel closure or lid.